From US 2010/0202243A1, a screw machine is known which has a vacuum filter insert for the feeding and treatment of bulk material which al-lows the bulk material to be degassed when a vacuum is applied thereto. This allows a powdery bulk material to be easily fed to the screw machine. In order to prevent bulk material from being discharged from the screw machine via the vacuum filter insert, the vacuum filter insert is provided with a filter element in the form of a metal nonwoven. A drawback is that the filter element only has a limited service life and needs to be replaced as soon as the service life has expired which results in unwanted downtimes for the screw machine.